Semiconductor memory device

ABSTRACT

A semiconductor memory device includes a semiconductor substrate, transistors formed in an upper surface of the semiconductor substrate, a stacked body provided on the semiconductor substrate, a first contact, and a second contact. The transistors are arranged along a first direction. A minimum period of an arrangement of the transistors is a first period. The stacked body includes electrode films. A configuration of a first portion of the stacked body is a staircase-like having terraces. A first region and a second region are set along the first direction in the first portion. A length in the first direction of the terrace disposed in the second region is longer than the first period. A length in the first direction of the terrace disposed in the first region is shorter than the first period.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/646,780, filed Jul. 11, 2017, which is based upon and claims thebenefit of priority from U.S. Provisional Patent Application 62/374,034,filed on Aug. 12, 2016; the entire contents of which are incorporatedherein by reference.

This application is based upon and claims the benefit of priority fromJapanese Patent Application No. 2017-016330, filed on Jan. 31, 2017; theentire contents of which are incorporated herein by reference.

FIELD

Embodiments relate to a semiconductor memory device.

BACKGROUND

In recent years, a stacked semiconductor memory device has been proposedin which memory cells are integrated three-dimensionally. In such astacked semiconductor memory device, a stacked body in which electrodefilms and insulating films are stacked alternately is provided on thesemiconductor substrate; and semiconductor pillars that pierce thestacked body are provided. Thereby, memory cell transistors are formedat each crossing portion between the electrode films and thesemiconductor pillars. On the other hand, transistors that switchbetween whether or not potentials are supplied to the electrode filmsare provided at the periphery of the stacked body. The end portion ofthe stacked body is patterned into a staircase configuration; a contactis connected to each of the electrode films; and the contacts areconnected to the transistors via upper layer interconnects. In such asemiconductor memory device, when the number of stacks of electrodefilms increases, the number of upper layer interconnects increases; andit becomes difficult to make the layout.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view showing a semiconductor memory deviceaccording to a first embodiment;

FIG. 2 is a plan view showing an interconnect portion of thesemiconductor memory device according to the first embodiment;

FIG. 3 is a plan view showing a substrate surface of the semiconductormemory device according to the first embodiment;

FIG. 4 is a partially enlarged cross-sectional view showing region A ofFIG. 1;

FIG. 5 is a plan view showing a semiconductor memory device according toa second embodiment;

FIG. 6 is a cross-sectional view along line B-B′ shown in FIG. 5;

FIG. 7 is a cross-sectional view along line C-C′ shown in FIG. 5;

FIG. 8 is a partially enlarged cross-sectional view showing region D ofFIG. 6;

FIG. 9 is a plan view showing a semiconductor memory device according toa third embodiment;

FIG. 10 is a cross-sectional view along line E-E′ shown in FIG. 9;

FIG. 11 is a cross-sectional view along line F-F′ shown in FIG. 9;

FIG. 12 is a plan view showing a semiconductor memory device accordingto a fourth embodiment;

FIG. 13 is a plan view showing a stacked body of a semiconductor memorydevice according to a fifth embodiment;

FIG. 14 is a plan view showing a semiconductor substrate of thesemiconductor memory device according to the fifth embodiment;

FIG. 15 is a cross-sectional view showing the semiconductor memorydevice according to the fifth embodiment;

FIG. 16 is a plan view showing a stacked body of a semiconductor memorydevice according to a sixth embodiment;

FIG. 17 is a plan view showing a semiconductor substrate of thesemiconductor memory device according to the sixth embodiment;

FIG. 18 is a cross-sectional view showing the semiconductor memorydevice according to the sixth embodiment;

FIG. 19 is a plan view showing a stacked body of a semiconductor memorydevice according to a seventh embodiment;

FIG. 20 is a plan view showing a semiconductor substrate of thesemiconductor memory device according to the seventh embodiment;

FIG. 21 is a cross-sectional view showing the semiconductor memorydevice according to the seventh embodiment;

FIG. 22 is a plan view showing a stacked body of a semiconductor memorydevice according to an eighth embodiment;

FIG. 23 is a plan view showing a semiconductor substrate of thesemiconductor memory device according to the eighth embodiment;

FIG. 24 is a cross-sectional view showing the semiconductor memorydevice according to the eighth embodiment;

FIG. 25 is a plan view showing a chip in which transistors of asemiconductor memory device according to a ninth embodiment are formed;

FIG. 26 is a plan view showing a chip in which a stacked body of thesemiconductor memory device according to the ninth embodiment is formed;

FIG. 27 is a cross-sectional view showing the semiconductor memorydevice according to the ninth embodiment;

FIG. 28 is a plan view showing a chip in which transistors of asemiconductor memory device according to a first modification of theninth embodiment are formed;

FIG. 29 is a plan view showing a chip in which a stacked body of thesemiconductor memory device according to the first modification of theninth embodiment is formed;

FIG. 30 is a cross-sectional view showing the semiconductor memorydevice according to the first modification of the ninth embodiment;

FIG. 31 is a plan view showing a chip in which transistors of asemiconductor memory device according to a second modification of theninth embodiment are formed;

FIG. 32 is a plan view showing a chip in which a stacked body of thesemiconductor memory device according to the second modification of theninth embodiment is formed; and

FIG. 33 is a cross-sectional view showing the semiconductor memorydevice according to the second modification of the ninth embodiment.

DETAILED DESCRIPTION

A semiconductor memory device according to an embodiment includes asemiconductor substrate, a plurality of transistors formed in an uppersurface of the semiconductor substrate, a stacked body provided on thesemiconductor substrate, a semiconductor member, a charge storage membera first contact, a second contact, and a first interconnect provided onthe first contact and the second contact, and connected between thefirst contact and the second contact. The plurality of transistors isarranged periodically along a first direction parallel to the uppersurface. A minimum period of the plurality of transistors is a firstperiod. The stacked body includes a plurality of electrode films stackedto be separated from each other along a vertical direction. Thesemiconductor member pierces the plurality of electrode films. Thecharge storage member is provided between the semiconductor member andone of the plurality of electrode films. A configuration of a firstportion of the stacked body is a staircase-like having a plurality ofterraces. The first portion is disposed in the region directly above theplurality of transistors. Each of the plurality of terraces is formedeach of the electrode films. The plurality of terraces includes aplurality of first terraces and a second terrace. A second region andtwo first regions are set along the first direction in the firstportion. The second region is disposed between the two first regions.The plurality of first terraces is disposed in each of the firstregions. The second terrace is disposed in the second region. A lengthin the first direction of the second terrace is longer than the firstperiod. A length in the first direction of one of the plurality of firstterraces is shorter than the first period. A lower end of the firstcontact is connected to one of the plurality of electrode films at oneof the terraces. The second contact pierces the stacked body. A lowerend of the second contact is connected to one of a source/drain of thetransistor.

(First Embodiment)

First, a first embodiment will be described.

FIG. 1 is a cross-sectional view showing a semiconductor memory deviceaccording to the embodiment.

FIG. 2 is a plan view showing the interconnect portion of thesemiconductor memory device according to the embodiment.

FIG. 3 is a plan view showing the substrate surface of the semiconductormemory device according to the embodiment.

FIG. 4 is a partially enlarged cross-sectional view showing region A ofFIG. 1.

The semiconductor memory device according to the embodiment is, forexample, a nonvolatile semiconductor memory device and is, for example,stacked NAND flash memory.

As shown in FIG. 1 to FIG. 3, a semiconductor substrate 10 is providedin the semiconductor memory device 1 according to the embodiment. In thespecification hereinbelow, an XYZ orthogonal coordinate system isemployed for convenience of description. Two mutually-orthogonaldirections parallel to an upper surface 10 a of the semiconductorsubstrate 10 are taken as an “X-direction” and a “Y-direction;” and adirection perpendicular to the upper surface of the semiconductorsubstrate 10 is taken as a “Z-direction.” Also, although a directionthat is in the Z-direction from the semiconductor substrate 10 toward astacked body 30 described below is called “up” and the reverse directionis called “down,” these expressions are for convenience and areindependent of the direction of gravity.

The semiconductor substrate 10 is formed of, for example, a monocrystalof silicon. For example, a p-type well 21 is formed in a portion of theupper layer portion of the semiconductor substrate 10. STI (ShallowTrench Isolation) 26 is provided in a lattice configuration in a portionof the upper layer portion of the well 21 and partitions the upper layerportion of the well 21 into multiple body regions 21 a. The body regions21 a are arranged in a matrix configuration along the X-direction andthe Y-direction. A field effect transistor 20 is provided in the uppersurface of each of the body regions 21 a, that is, in the region of theupper surface 10 a of the semiconductor substrate 10 surrounded with theSTI 26. N-type diffusion regions 22 and 23 are formed to be separatedfrom each other in the upper portions of the two Y-direction endportions of each of the body regions 21 a. The diffusion regions 22 and23 are source/drain regions of the transistor 20. Also, a gateinsulating film 24 is provided on the well 21; and a gate electrode 25is provided on the gate insulating film 24.

The arrangement period of the transistors 20 in the X-direction issubstantially constant. More specifically, multiple transistors 20 areprovided inside a prescribed region of the upper surface 10 a of thesemiconductor substrate 10; and inside this region, the arrangementperiod of the transistors 20 in the X-direction is constant. In thespecification, this arrangement period is called the “minimumarrangement period.” Although only one of these regions is shown in theembodiment, there are also cases where this region is multiply providedas in a ninth embodiment described below. In such a case, the distancebetween the mutually-adjacent regions is larger than the spacing betweenthe transistors 20 determined by the minimum arrangement period. Thearrangement period of the transistors 20 is, for example, an arrangementperiod of the end edges facing one side in the X direction of the bodyregion 21 a.

Contacts 27, lower layer interconnects 28, and a source line 29 areprovided, from the bottom toward the top, on the semiconductor substrate10, i.e., on the transistors 20. The lower layer interconnects 28 aremultiply provided and may be connected to each other by via contacts.The lower end of the contact 27 is connected to the diffusion region 22;and the upper end of the contact 27 is connected to the lower layerinterconnect 28. The source line 29 is provided on the lower layerinterconnects 28; and the configuration of the source line 29 is a plateconfiguration spreading along the XY plane.

The stacked body 30 is provided on the source line 29. The insulatingfilms 31 and electrode films 32 are stacked alternately along theZ-direction in the stacked body 30. The insulating films 31 are formedof, for example, an insulating material such as silicon oxide (SiO),etc.; and the electrode films 32 are formed of, for example, aconductive material such as tungsten (W), polysilicon (Si) to which animpurity is introduced, etc. The transistors 20 are transistors fordriving the electrode films 32. Other than the transistors 20, forexample, transistors that are included in a peripheral circuit (notillustrated) may be provided in the semiconductor memory device 1.

As shown in FIG. 2, the electrode films 32 are subdivided into multipleband-like portions arranged along the Y-direction. Each of the band-likeportions extends in the X-direction. In the embodiment, the band-likeportions of the electrode film 32 of the lowermost layer function assource-side selection gates SGS; the band-like portions of the electrodefilm 32 of the uppermost layer function as drain-side selection gatesSGD; and the band-like portions of the other electrode films 32 functionas word lines WL. The band-like portions of the electrode films 32 ofmultiple layers from the lowermost layer may function as the source-sideselection gates SGS; and the band-like portions of the electrode films32 of multiple layers from the uppermost layer may function as thedrain-side selection gates SGD. The arrangement period of the drain-sideselection gates SGD in the Y-direction is half of the arrangement periodof the source-side selection gates SGS and the word lines WL. In otherwords, two drain-side selection gates SGD are disposed in the regiondirectly above one word line WL. One, three, or more drain-sideselection gates SGD may be disposed in the region directly under oneword line WL.

The configuration of an end portion 30 a in the X-direction of thestacked body 30 is a staircase-like in which a terrace is formed everyelectrode film 32. The terrace is the upper surface of the X-directionend portion of the electrode film 32. The electrode films 32 of thelayers above a terrace are not disposed in the region directly above theterrace. The end portion 30 a is disposed in the region directly abovethe transistors 20. On the other hand, a central portion 30 b in theX-direction of the stacked body 30 is not disposed in the regiondirectly above the transistors 20.

The upper surface of the end portion 30 a descends, in stages andwithout increasing partway, along the direction from the X-directioncentral portion 30 b toward the end portion 30 a of the stacked body 30.However, the descent is not periodic. Specifically, regions R1 andregions R2 are arranged alternately along the X-direction in the endportion 30 a. In the region R1, multiple terraces 33 a that have narrowwidths are arranged along the X-direction. On the other hand, in theregion R2, one terrace 33 b that has a wide width is disposed. A lengthL2 of the terrace 33 b in the X-direction is longer than a length L1 ofthe terrace 33 a in the X-direction. Also, in the X-direction, thelength L1 of the terrace 33 a is shorter than a minimum arrangementperiod P of the transistors 20; and the length L2 of the terrace 33 b islonger than the minimum arrangement period P of the transistors 20. Inother words, L1<P<L2.

An insulating film 40 is provided on the semiconductor substrate 10 tocover the stacked body 30. Multiple contacts 41 and multiple contacts 42are provided inside the insulating film 40. Upper layer word lines 43are connected respectively between the upper ends of the contacts 41 andthe upper ends of the contacts 42. The upper layer word lines 43 aredisposed higher than the stacked body 30 inside the insulating film 40.

The contacts 41 extend in the Z-direction; and the lower ends of thecontacts 41 are connected to the electrode films 32 at the terraces 33 aor the terraces 33 b. Accordingly, among the electrode films 32, theelectrode films 32 that have the terraces 33 a inside the region R1 areconnected to the contacts 41 inside the region R1. On the other hand,the electrode films 32 that have the terraces 33 b inside the region R2are connected to the contacts 41 inside the region R2. Therefore, thecontacts 41 are disposed in both the region R1 and the region R2.

The contacts 42 are disposed inside the region R2. The contacts 42extend in the Z-direction and pierce the source line 29 and the endportion 30 a of the stacked body 30. The lower ends of the contacts 42are connected to the lower layer interconnects 28. An insulating film 44is provided at the peripheries of the contacts 42. The contacts 42 areinsulated from the electrode films 32 and the source line 29 by theinsulating film 44.

Thus, each of the electrode films 32 is connected to the diffusionregion 22 of the transistor 20 via the contact 41, the upper layer wordline 43, the contact 42, the lower layer interconnect 28, and thecontact 27. Also, the electrode films 32 that have the terraces 33 ainside the region R1 are connected to the diffusion regions 22 via thecontacts 41 inside the region R1 and the contacts 42 inside the regionR2. The electrode films 32 that have the terraces 33 b inside the regionR2 are connected to the diffusion regions 22 via the contacts 41 insidethe region R2 and the contacts 42 inside the region R2.

On the other hand, silicon pillars 50 that extend in the Z-direction areprovided inside the central portion 30 b of the stacked body 30. Thesilicon pillars 50 are made of, for example, polysilicon; and theconfigurations of the silicon pillars 50 are circular tubes havingplugged lower ends. The lower ends of the silicon pillars 50 areconnected to the source line 29. The upper ends of the silicon pillars50 are connected to bit lines 47 by via contacts 46. The bit lines 47are disposed on the central portion 30 b of the stacked body 30 andextend in the Y-direction. A structure (not shown) similar to thesilicon pillar 50 is also provided in the end portion 30 a of thestacked body 30. This structure is not connected to the bit line 47 anddoes not function electrically. This structure functions as a supportcolumn for supporting the stacked body 30 in the manufacturing processof the semiconductor memory device 1.

As shown in FIG. 4, a core member 51 that is made of, for example,silicon oxide is provided inside the silicon pillar 50. The core member51 may not be provided. A tunneling insulating film 52 is provided onthe side surface of the silicon pillar 50. Although the tunnelinginsulating film 52 normally is insulative, the tunneling insulating film52 is a film in which a tunneling current flows when a prescribedvoltage within the range of the drive voltage of the semiconductormemory device 1 is applied. The tunneling insulating film 52 includes,for example, a single-layer silicon layer, or an ONO film in which asilicon oxide layer, a silicon nitride layer, and a silicon oxide layerare stacked in this order.

A charge storage film 53 is provided on the surface of the tunnelinginsulating film 52. The charge storage film 53 is a film that can storecharge, is formed of, for example, a material having trap sites ofelectrons, and is formed of, for example, silicon nitride (SiN).

A blocking insulating film 54 is provided on the surface of the chargestorage film 53. The blocking insulating film 54 is a film in which acurrent substantially does not flow even when a voltage within the rangeof the drive voltage of the semiconductor memory device 1 is applied.The blocking insulating film 54 is, for example, a two-layer film inwhich a silicon oxide layer and an aluminum oxide layer are stacked fromthe charge storage film 53 side.

A memory film 55 that can store data includes the tunneling insulatingfilm 52, the charge storage film 53, and the blocking insulating film54. Accordingly, the memory film 55 is disposed between the siliconpillar 50 and the electrode films 32.

Thereby, a memory cell transistor MC that has a MONOS(Metal-Oxide-Nitride-Oxide-Silicon) structure with the memory film 55interposed is configured at each crossing portion between the siliconpillars 50 and the word lines WL. The memory cell transistors MC arearranged in a three-dimensional matrix configuration because the siliconpillars 50 are arranged in a matrix configuration along the X-directionand the Y-direction and because the word lines WL are arranged along theZ-direction. Thereby, a NAND string in which the multiple memory celltransistors MC are connected in series is formed between the bit line 47and the source line 29. Also, any memory cell transistor MC can beselected by selectively applying potentials to the word lines WL, etc.,by switching the transistors 20 ON/OFF.

Effects of the embodiment will now be described.

In the semiconductor memory device 1 according to the embodiment, thetransistors 20 that select the word lines WL, etc., are disposed betweenthe semiconductor substrate 10 and the stacked body 30. Thereby, thechip surface area can be reduced compared to the case where thetransistors 20 are disposed at the periphery of the stacked body 30. Asa result, the integration of the semiconductor memory device 1 can beincreased; and the cost can be reduced.

Also, in the embodiment, in the X-direction end portion 30 a of thestacked body 30, the regions R1, in which the terraces 33 a that arenarrower than the minimum arrangement period P of the transistors 20 areformed, and the regions R2, in which the terraces 33 b that are widerthan the minimum arrangement period P are formed, are arrangedalternately. Thereby, the minimum arrangement period P of thetransistors 20 and the average arrangement period of the terraces 33 aand 33 b substantially match; and the connections between the electrodefilms 32 and the transistors 20 are easy. Also, the contacts 41 that aredisposed in the region R1 are drawn out to the region R2 by the upperlayer word lines 43 and are connected to the diffusion regions 22 viathe contacts 42 piercing the stacked body 30 disposed in the region R2.Thereby, the arrangement density of the contacts 42 can be reduced byeffectively utilizing the region R2. As a result, the layout of thecontacts 41, the contacts 42, and the upper layer word lines 43 is easy.

The semiconductor memory device 1 is not enlarged even in the case wherethe region R2 is provided because the length in the X-direction of theregion necessary for arranging the multiple transistors 20 is longerthan the length in the X-direction of the end portion 30 a.

Further, when patterning the end portion 30 a of the stacked body 30into the staircase configuration, the stacked body 30 is formed on theentire surface of the semiconductor substrate 10; a resist film isformed on the stacked body 30; subsequently, the terraces are formed bypartially removing the electrode films 32 one layer at a time byalternately performing etching using the resist film as a mask andslimming of the resist film. In such a case, although the width of theterrace widens as the slimming amount of one slimming of the resist filmincreases, it is necessary to set the initial height of the resist filmto be high; and the patterning is difficult.

Therefore, in the embodiment, a unit process that includes the formingof the resist film, the multiple repeating of the slimming and theetching, and the removing of the resist film is multiply implemented.Thereby, the multiple terraces 33 a are formed in one region R1 by oneunit process or multiple unit processes implemented continuously. Then,the region between the final patterned end of one or multiple unitprocesses for forming some region R1 and the initial patterned end ofone or multiple unit processes for forming the next region R1 becomesthe region R2. Thus, compared to the case where terraces of uniformwidths are formed, the slimming amount of one slimming can be reduced;and the initial height of the resist film can be reduced. As a result,the manufacturing of the semiconductor memory device 1 is easy.

(Second Embodiment)

A second embodiment will now be described.

FIG. 5 is a plan view showing a semiconductor memory device according tothe embodiment.

FIG. 6 is a cross-sectional view along line B-B′ shown in FIG. 5.

FIG. 7 is a cross-sectional view along line C-C′ shown in FIG. 5.

FIG. 8 is a partially enlarged cross-sectional view showing region D ofFIG. 6.

As shown in FIG. 5 to FIG. 7, the semiconductor memory device 2according to the embodiment differs from the semiconductor memory device1 according to the first embodiment described above (referring to FIG. 1to FIG. 4) in that transistors 20 a are provided instead of thetransistors 20. One diffusion region 23 is provided between twodiffusion regions 22 in the transistor 20 a. A contact (not illustrated)for supplying a source potential to the transistor 20 is connected tothe diffusion region 23. Also, two gate electrodes 25 are provided andare disposed in the regions directly above the regions of the well 21between the diffusion region 23 and the diffusion regions 22. Thereby,two transistor elements that are driven independently are includedinside one transistor 20 a.

Also, in the semiconductor memory device 2, the staircase of the endportion 30 a is formed not only along the X-direction but also along theY-direction. Accordingly, the terraces 33 a and 33 b are arranged in achessboard-like configuration when viewed from the Z-direction. Thereby,the length in the X-direction of the end portion 30 a can be shortened.Similarly to the first embodiment described above, the upper surface ofthe end portion 30 a descends, at any position in the Y-direction, instages and without increasing partway, along the X-direction from thecentral portion 30 b toward the end portion 30 a of the stacked body 30,that is, along a direction away from the silicon pillars 50.

Further, in the semiconductor memory device 2, the multiple word linesWL that are arranged in the Y-direction are drawn out alternately to thetwo X-direction sides of the central portion 30 b. In other words, whenthe multiple word lines WL that are arranged along the Y-direction arealternately named word lines WL_A and word lines WL_B, in the endportion 30 a shown in FIG. 5 to FIG. 7, the contacts 41 are connected toonly the word lines WL_A. On the other hand, at the end portion 30 a onthe opposite side of the stacked body 30 in the X-direction (notillustrated), the word lines WL_B are connected to the contacts 41.Thus, by drawing out the word lines WL alternately to the twoX-direction sides of the stacked body 30, the layout of the contacts 41and the upper layer word lines 43 can have ample margin.

As described above, in the end portion 30 a shown in FIG. 5 to FIG. 7,the contacts 41 are connected to only the word lines WL_A. Accordingly,the contacts 41 are disposed only in the regions directly above the wordlines WL_A. On the other hand, the contacts 42 pierce the word linesWL_B. Therefore, the upper layer word lines 43 extend from the regionsdirectly above the word lines WL_A to the regions directly above theword lines WL_B. In other words, portions that extend in the Y-directionexist in the upper layer word lines 43. Thus, in the semiconductormemory device 2, the contacts 41 that are disposed in the regionsdirectly above the word lines WL_A are drawn out to the regions directlyabove the word lines WL_B by the upper layer word lines 43 and areconnected to the diffusion regions 22 of the transistors 20 a via thecontacts 42. Thereby, the constraints of the layout of the contacts 41,the contacts 42, and the upper layer word lines 43 are relaxed becausethe contacts 41 and the contacts 42 can be arranged to be dispersed inthe Y-direction.

Also, in the embodiment as well, similarly to the first embodimentdescribed above, some of the contacts 41 disposed in the region R1 areconnected to the contacts 42 disposed in the region R2. Thereby, theconstraints of the arrangement of the contacts 42 in the X-direction arerelaxed. Thereby, the layout of the contacts 41, the contacts 42, andthe upper layer word lines 43 is easy. The contacts 41, the contacts 42,and the upper layer word lines 43 are arranged similarly in the endportion 30 a on the opposite X-direction side (not illustrated) as well.

Further, contacts 48 are provided on the diffusion regions 23 of thetransistors 20 a. The lower ends of the contacts 48 are connected to thediffusion regions 23. The contacts 48 extend in the Z-direction andpierce the source line 29 and the end portion 30 a of the stacked body30. However, the contacts 48 are insulated from the source line 29 andthe electrode films 32. An upper layer source line 49 is provided on thecontacts 48. The upper ends of the contacts 48 are connected to theupper layer source line 49. For example, the upper layer source line 49extends in the Y-direction. In FIG. 5 and FIG. 6, only one upper layersource line 49 is shown for easier viewing of the drawing.

As shown in FIG. 8, a floating electrode-type memory cell transistor MCis formed in the semiconductor memory device 2 according to theembodiment. In other words, a floating gate electrode 56 that is madeof, for example, a conductive material such as polysilicon or the likeis provided between the electrode film 32 and the columnar body made ofthe core member 51, the silicon pillar 50, and the tunneling insulatingfilm 52. The configuration of the floating gate electrode 56 is acircular ring configuration surrounding the tunneling insulating film52. The floating gate electrode 56 functions as a charge storage member.The blocking insulating film 54 is provided between the floating gateelectrode 56 and the electrode film 32. For example, an aluminum oxidelayer 54 a that covers the upper surface of the floating gate electrode56, the lower surface of the floating gate electrode 56, and the sidesurface of the floating gate electrode 56 on the electrode film 32 sideis provided in the blocking insulating film 54; an aluminum oxide layer54 c that covers the upper surface of the electrode film 32, the lowersurface of the electrode film 32, and the side surface of the electrodefilm 32 on the floating gate electrode 56 side is provided in theblocking insulating film 54; and a silicon oxide layer 54 b that isdisposed between the aluminum oxide layer 54 a and the aluminum oxidelayer 54 c is provided in the blocking insulating film 54.

Effects of the embodiment will now be described.

In the embodiment, the contacts 41 are disposed in the regions directlyabove the word lines WL_A; the contacts 42 are disposed in the placementregions of the word lines WL_B; and the upper ends of the contacts 41and the upper ends of the contacts 42 are connected by the upper layerword lines 43. Thereby, the word lines WL_A can be connected to thediffusion regions 22 by effectively utilizing the placement regions ofthe word lines WL_B which are originally dead space. As a result, thespacing between the contacts 41 and the contacts 42 can be ensured; andthe layout can be made easily. Otherwise, the configuration and theeffects of the embodiment are similar to those of the first embodimentdescribed above.

(Third Embodiment)

A third embodiment will now be described.

FIG. 9 is a plan view showing a semiconductor memory device according tothe embodiment.

FIG. 10 is a cross-sectional view along line E-E′ shown in FIG. 9.

FIG. 11 is a cross-sectional view along line F-F′ shown in FIG. 9.

In the semiconductor memory device 3 according to the embodiment asshown in FIG. 9 to FIG. 11, the source line 29 (referring to FIG. 1) isnot provided; and the lower ends of the silicon pillars 50 are connectedto the semiconductor substrate 10. Also, in the end portion 30 a of thestacked body 30, a slit 60 that extends in the X-direction is formedbetween the word lines WL and between the source-side selection gatesSGS adjacent to each other in the Y-direction. Inside the slit 60, theelectrode films 32 are not disposed; and the insulating film 40 isfilled. Also, the transistors 20 a are formed only in the regiondirectly under the slit 60; and the contacts 42 are disposed inside theslit 60. On the other hand, the contacts 41 are disposed in the regionsdirectly above the electrode films 32. Thus, the contacts 41 and thecontacts 42 are separated in the Y-direction. Accordingly, portions thatextend in the Y-direction exist in all of the upper layer word lines 43;and portions that extend in the X-direction also exist in some of theupper layer word lines 43. Also, in the embodiment as well, a staircasealong the X-direction is formed in the end portion 30 a of the stackedbody 30.

In the semiconductor memory device 3 according to the embodiment, thesource line 29 is not provided; and the semiconductor substrate 10functions as the source line. Thereby, the number of manufacturingprocesses and/or patterning time of the semiconductor memory device 4can be suppressed; and the manufacturing is easy. Also, the interferencebetween the electrode films 32 on the lower layer side and the upperstructure bodies and accessory structure bodies of the transistors 20 asuch as the gate electrodes 25, the contacts 27, the lower layerinterconnects 28, etc., can be avoided by providing the slit 60 in theend portion 30 a of the stacked body 30 and by disposing the transistors20 a in the region directly under the slit 60. Also, the arrangement ofthe contacts 41 and 42 and the draw-out of the upper layer word lines 43are easy because the regions where the contacts 41 are disposed and theregions where the contacts 42 are disposed are separated. Otherwise, theconfiguration and the effects of the embodiment are similar to those ofthe second embodiment described above.

(Fourth Embodiment)

A fourth embodiment will now be described.

FIG. 12 is a plan view showing a semiconductor memory device accordingto the embodiment.

In the semiconductor memory device 4 according to the embodiment asshown in FIG. 12, multiple word lines WL that are arranged along theY-direction are connected to the diffusion region 22 of one transistor20. For example, two contacts 41 that are connected to two word lines WLadjacent to each other in the Y-direction and one contact 42 that isconnected to the diffusion region 22 of one transistor 20 are connectedto one upper layer word line 43.

According to the embodiment, the number of the transistors 20 can bereduced. Otherwise, the configuration and the effects of the embodimentare similar to those of the first embodiment described above.

(Fifth Embodiment)

A fifth embodiment will now be described.

FIG. 13 is a plan view showing the stacked body of a semiconductormemory device according to the embodiment.

FIG. 14 is a plan view showing the semiconductor substrate of thesemiconductor memory device according to the embodiment.

FIG. 15 is a cross-sectional view showing the semiconductor memorydevice according to the embodiment.

In the semiconductor memory device 5 according to the embodiment asshown in FIG. 13 to FIG. 15, the transistors 20 of one memory block arearranged in multiple rows not only along the X-direction but also alongthe Y-direction. Also, the diffusion region 22 of one transistor 20 isconnected to multiple, e.g., four electrode films 32. The contacts 42are disposed in the region R2 and are arranged in one column along theX-direction. In the embodiment as well, the length L1 of the terrace 33a in the X-direction is shorter than the minimum arrangement period P ofthe transistors 20; and the length L2 of the terrace 33 b is longer thanthe minimum arrangement period P of the transistors 20. In other words,L1<P<L2 holds.

The configuration of the semiconductor memory device 5 will now bedescribed in detail.

In the semiconductor memory device 5, the electrode films 32 of thirteenlayers arranged along the Z-direction are provided. These electrodefilms 32 are taken as electrode films 32 c to 32 o in order from thelower layer side. The electrode films 32 c of the lowermost layer arethe source-side selection gates SGS. In one memory block, four of theelectrode films 32 c are arranged along the Y-direction and areconnected to the same transistor 20. The electrode films from theelectrode films 32 d that are second from the lowermost layer to theelectrode films 32 n that are second from the uppermost layer are theword lines WL. In one memory block, the electrode films 32 d to 32 neach are arranged along the Y-direction and are connected respectivelyto the same transistors 20.

The electrode films 32 o of the uppermost layer are the drain-sideselection gates SGD. In one memory block, eight of the electrode films32 o are arranged along the Y-direction and are connected tomutually-different transistors 20. The eight electrode films 32 obelonging to the one memory block also are called electrode films 32 o 1to 3208. The arrangement period of the drain-side selection gates SGD inthe Y-direction is half of the arrangement period of the word lines WL.Accordingly, two drain-side selection gates SGD are disposed in theregion directly above one word line WL.

Twenty transistors 20 are provided in the semiconductor memory device 5.These transistors 20 are taken as transistors 20 c to 20 v. Also, thediffusion region 22 of the transistor 20 c is taken as a diffusionregion 22 c. Further, the contact 27, the lower layer interconnect 28,the contact 42, the upper layer word line 43, and the contact 41 thatare connected to the transistor 20 c are respectively taken as a contact27 c, a lower layer interconnect 28 c, a contact 42 c, an upper layerword line 43 c, and a contact 41 c. This is similar for transistors 20 dto 20 v as well.

The diffusion region 22 c of the transistor 20 c is drawn outsubstantially directly upward by the contact 27 c, the lower layerinterconnect 28 c, and the contact 42 c, is drawn out in the Y-directionby the upper layer word line 43 c, goes halfway around in a U-shapedconfiguration, and is connected to four electrode films 32 c (thesource-side selection gates SGS) via four contacts 41 c.

The transistor 20 d is disposed on the Y-direction side when viewed fromthe transistor 20 c. A diffusion region 22 d of the transistor 20 d isdrawn out to the region directly above the diffusion region 22 c by alower layer interconnect 28 d, is drawn out directly upward by a contact42 d, goes halfway around outside the upper layer word line 43 c by anupper layer word line 43 d, and is connected to four electrode films 32d (the word lines WL) via four contacts 41 d.

A transistor 20 e is disposed on the X-direction side when viewed fromthe transistor 20 d. A diffusion region 22 e of the transistor 20 e isdrawn out to the region directly above a diffusion region 22 f by alower layer interconnect 28 e, is drawn out directly upward by a contact42 e, goes halfway around in the reverse direction of the upper layerword line 43 d by an upper layer word line 43 e, and is connected tofour electrode films 32 e (the word lines WL) via four contacts 41 e.

The transistor 20 f is disposed on the Y-direction side when viewed fromthe transistor 20 e. The diffusion region 22 f of the transistor 20 f isdrawn out substantially directly upward by a contact 27 f, a lower layerinterconnect 28 f, and a contact 42 f, goes halfway around inside theupper layer word line 43 e by an upper layer word line 43 f, and isconnected to four electrode films 32 f (the word lines WL) via fourcontacts 41 f.

Thus, the transistors 20 c to 20 f are connected respectively to thefour electrode films 32 c to 32 f. Also, the diffusion regions 23 of thetransistors 20 c to 20 f are connected to lower layer interconnects 39.The lower layer interconnects 39 extend substantially in theY-direction. The positions in the Z-direction of the lower layerinterconnects 39 are the same as the positions in the Z-direction of thelower layer interconnects 28. The main line portions of the lower layerinterconnects 39 may be upper layer interconnects; and in such a case,the lower layer interconnects 39 are connected to the upper layerinterconnects used as the main line portions via additional contacts.

The transistors 20 g to 20 j are connected respectively to the fourelectrode films 32 g to 32 j by a halfway-around interconnect patternsimilar to the current paths from the transistors 20 c to 20 f to theelectrode films 32 c to 32 f. Also, the transistors 20 k to 20 n areconnected respectively to the four electrode films 32 k to 32 n by asimilar halfway-around interconnect pattern.

A diffusion region 22 o of the transistor 20 o is drawn outsubstantially directly upward by a contact 27 o, a lower layerinterconnect 28 o, and a contact 42 o, is drawn out in the Y-directionby an upper layer word line 43 o, subsequently is drawn out in theX-direction, and is connected to one electrode film 32 o 2 (thedrain-side selection gate SGD) via one contact 410. When viewed from theZ-direction, the configuration of the upper layer word line 43 o is anL-shaped configuration.

A diffusion region 22 p of the transistor 20 p is drawn out to theregion directly above the diffusion region 22 o by a lower layerinterconnect 28 p, is drawn out directly upward by a contact 42 p, isdrawn out in an L-shaped configuration outside the upper layer word line43 o by an upper layer word line 43 p, and is connected to one electrodefilm 32 o 1 (the drain-side selection gate SGD) via one contact 41 p.

By an interconnect pattern having an L-shaped configuration similar tothe current paths from the transistors 20 o and 20 p to the electrodefilms 32 o 2 and 32 o 1, a diffusion region 22 q of the transistor 20 qis connected to the electrode film 32 o 4; and a diffusion region 22 rof the transistor 20 r is connected to the electrode films 3203.

A diffusion region 22 s of the transistor 20 s is connected to theelectrode film 32 o 7 and a diffusion region 22 t of the transistor 20 tis connected to the electrode film 3208 by an interconnect patternhaving a similar L-shaped configuration. Also, a diffusion region 22 uof the transistor 20 u is connected to the electrode film 32 o 5; and adiffusion region 22 v of the transistor 20 v is connected to theelectrode film 32 o 6.

Effects of the embodiment will now be described.

In the embodiment, the placement region of the transistors 20 and thelength in the X-direction of the end portion 30 a of the stacked body 30can be shortened because the transistors 20 are arranged not only in theX-direction but also in the Y-direction.

Otherwise, the configuration and the effects of the embodiment aresimilar to those of the first embodiment described above.

(Sixth Embodiment)

A sixth embodiment will now be described.

FIG. 16 is a plan view showing the stacked body of a semiconductormemory device according to the embodiment.

FIG. 17 is a plan view showing the semiconductor substrate of thesemiconductor memory device according to the embodiment.

FIG. 18 is a cross-sectional view showing the semiconductor memorydevice according to the embodiment.

In the semiconductor memory device 6 according to the embodiment asshown in FIG. 16 to FIG. 18, the staircase of the end portion 30 a isformed along not only the X-direction but also the Y-direction. Thestaircase along the X-direction is formed over all of the electrodefilms 32 arranged along the Z-direction; and one step is formed everytwo electrode films 32. The staircase along the Y-direction is formed tocorrespond to only one electrode film 32; and one step is formed for theone electrode film 32. In other words, in the stacked body 30, (n/2)levels of steps are formed by being formed every two electrode films 32along the X-direction, and only one level of steps corresponding to oneelectrode film 32 is formed along the Y-direction, where n is the numberof the electrode films 32 arranged along the Z-direction. Thereby, theterraces can be formed for all of the n electrode films 32. When theentire end portion 30 a is viewed, the configuration of a region H wherethe terraces are disposed one level higher than the terraces adjacent inthe Y-direction is a comb-shaped configuration when viewed from theZ-direction.

Also, in the semiconductor memory device 6, every two word lines WL ofthe multiple word lines WL arranged along the Y-direction are drawn outalternately to the two X-direction sides of the stacked body 30. Inother words, in the end portion 30 a shown in FIG. 16 to FIG. 18, thecontacts 41 are connected to only the word lines WL_A when the multipleword lines WL arranged along the Y-direction are taken as the word lineWL_A, the word line WL_A, the word line WL_B, the word line WL_B, theword line WL_A, the word line WL_A, . . . . On the other hand, thecontacts 41 are connected to the word lines WL_B at the end portion 30 aon the opposite side (not illustrated).

Further, in the semiconductor memory device 6, similarly to thesemiconductor memory device 5 according to the fifth embodimentdescribed above (referring to FIG. 13 to FIG. 15), the transistors 20are arranged not only along the X-direction but also along theY-direction. Also, for example, the diffusion region 22 of onetransistor 20 is connected to two electrode films 32.

Also, in the end portion 30 a shown in FIG. 16 to FIG. 18, the contacts41 are disposed in the regions directly above the word lines WL_A. Onthe other hand, the contacts 42 are disposed at positions piercing theword lines WL_B. Therefore, the upper layer word lines 43 extend fromthe regions directly above the word lines WL_A to the regions directlyabove the word lines WL_B. Accordingly, portions that extend in theY-direction exist in the upper layer word lines 43. The contacts 42 arearranged in one column along the X-direction.

Similarly to the word lines WL, the source-side selection gates SGS alsoare drawn out alternately two at a time to the two X-direction sides ofthe stacked body 30. The drain-side selection gates SGD are drawn outalternately four at a time to the two X-direction sides of the stackedbody 30.

Effects of the embodiment will now be described.

In the end portion 30 a of the stacked body 30 in the embodiment, a substaircase is formed along the Y-direction in addition to the mainstaircase along the X-direction. Thereby, the length in the X-directionof the end portion 30 a can be shortened.

Also, in the embodiment, the electrode films 32 are drawn outalternately to the two X-direction sides of the stacked body 30.Thereby, the number of the transistors 20 formed in the region directlyunder one end portion 30 a can be half compared to the case where theelectrode films 32 are drawn out to only one X-direction side. As aresult, the layout of the upper layer word lines 43, etc., is madeeasily.

Further, in the embodiment, the contacts 41 are disposed in the regionsdirectly above the word lines WL_A; and the contacts 42 are disposed inthe placement regions of the word lines WL_B. Thereby, the interconnectscan be drawn out by effectively utilizing the placement regions of theword lines WL_B which are originally dead space.

Otherwise, the configuration and the effects of the embodiment aresimilar to those of the first embodiment described above.

(Seventh Embodiment)

A seventh embodiment will now be described.

FIG. 19 is a plan view showing the stacked body of a semiconductormemory device according to the embodiment.

FIG. 20 is a plan view showing the semiconductor substrate of thesemiconductor memory device according to the embodiment.

FIG. 21 is a cross-sectional view showing the semiconductor memorydevice according to the embodiment.

As shown in FIG. 19 to FIG. 21, the semiconductor memory device 7according to the embodiment differs from the semiconductor memory device6 according to the sixth embodiment described above (referring to FIG.16 to FIG. 18) in that the configuration of the region H is an islandconfiguration. As described above, the region H is the region where theterraces are disposed one level higher than the terraces adjacent in theY-direction.

Thereby, in the embodiment, compared to the sixth embodiment, theelectrode films 32 that are connected between the transistors 20adjacent to each other in the Y-direction are reversed. Also, the endedge on the central portion 30 b side of the region H in the directionfrom the central portion 30 b toward the end portion 30 a of the stackedbody 30 is a step US that is one level higher. However, the step US is aconfiguration that occurs due to the patterning; and the electrode film32 that has the step US as an end surface does not function electricallyand is insulated and isolated from the electrode films that actuallyfunction. Similarly to the other embodiments, the electrode films thatactually function descend, in stages and without increasing partway, inthe direction from the central portion 30 b toward the end portion 30 a.Multiple levels of the terraces that are arranged along the Y-directionmay be formed similarly to the terraces arranged along the X-direction.

In the embodiment, the word lines WL and the drain-side selection gatesSGD that are arranged along the Y-direction can be formed by the sameprocess; and the number of processes can be reduced.

Otherwise, the configuration and the effects of the embodiment aresimilar to those of the sixth embodiment described above.

(Eighth Embodiment)

An eighth embodiment will now be described.

FIG. 22 is a plan view showing the stacked body of a semiconductormemory device according to the embodiment.

FIG. 23 is a plan view showing the semiconductor substrate of thesemiconductor memory device according to the embodiment.

FIG. 24 is a cross-sectional view showing the semiconductor memorydevice according to the embodiment.

As shown in FIG. 22 to FIG. 24, compared to the semiconductor memorydevice 6 according to the seventh embodiment described above (referringto FIG. 19 to FIG. 21), the arrangement of the contacts 41 and 42 of thesemiconductor memory device 8 according to the embodiment is different.

For each of the source-side selection gates SGS and the word lines WL inthe semiconductor memory device 8, the two contacts 41 that areconnected to two terraces arranged along the Y-direction and the twocontacts 42 connected to these contacts 41 via the upper layer wordlines 43 are arranged in one column along the Y-direction. In otherwords, in the X-direction, the positions of the two contacts 41 and thepositions of the two contacts 42 are equal to each other. For thedrain-side selection gates SGD, the four contacts 41 that are connectedto two terraces arranged along the Y-direction are arranged in onecolumn along the Y-direction; and the four contacts 42 that areconnected to these four contacts 41 also are arranged in one columnalong the Y-direction. In other words, the positions of the fourcontacts 41 in the X-direction are equal to each other; and thepositions of the four contacts 42 also are equal to each other. However,in the X-direction, the positions of the contacts 41 and the positionsof the contacts 42 are different from each other.

Otherwise, the configuration and the effects of the embodiment aresimilar to those of the seventh embodiment described above.

(Ninth Embodiment)

A ninth embodiment will now be described.

FIG. 25 is a plan view showing a chip in which the transistors of thesemiconductor memory device according to the embodiment are formed.

FIG. 26 is a plan view showing a chip in which the stacked body of thesemiconductor memory device according to the embodiment is formed.

FIG. 27 is a cross-sectional view showing the semiconductor memorydevice according to the embodiment.

In the semiconductor memory device 9 according to the embodiment asshown in FIG. 25 to FIG. 27, two chips 101 and 102 are bonded with bumps103 interposed. The stacked body 30 is provided in the chip 101. Thetransistors 20 are formed in the chip 102. Then, the electrode films 32that are provided in the chip 101 are connected, with the bumps 103interposed, to the transistors 20 formed in the chip 102. In thesemiconductor memory device 9, the upper surface sides of the chip 102shown in FIG. 25 and the chip 101 shown in FIG. 26 are bonded to opposeeach other. Although FIG. 27 shows the cross section including thecenters of the bumps 103, FIG. 27 also shows the lower layerinterconnects 28 and the contacts 42 for convenience of description.

This will now be described in more detail.

In the chip 101, a semiconductor substrate 11 that is made of, forexample, silicon is provided; the stacked body 30 is provided on thesemiconductor substrate 11; and the insulating film 40 is provided tocover the stacked body 30. However, the transistors 20 are not formed inthe semiconductor substrate 11; and the source line 29 (referring toFIG. 24) is not provided between the semiconductor substrate 11 and thestacked body 30. Also, the contacts 41 are provided on the terraces ofthe electrode films 32 of the stacked body 30; the upper layer wordlines 43 are provided on the contacts 41; and the upper ends of thecontacts 41 are connected to the upper layer word lines 43. However, thecontacts 42 (referring to FIG. 24) are not provided. Pads 64 areprovided in the upper layer portion of the insulating film 40 and areexposed at the upper surface of the inter-layer 40. The pads 64 areformed of, for example, copper. Contacts 63 are connected between theupper layer word lines 43 and the pads 64.

In the embodiment, similarly to the sixth embodiment described above(referring to FIG. 16 to FIG. 18), the electrode films 32 are drawn outto the two X-direction sides of the stacked body 30. In other words, themultiple source-side selection gates SGS and the multiple word lines WLthat are arranged along the Y-direction are drawn out alternately two ata time to the two X-direction sides of the stacked body 30. Also, themultiple drain-side selection gates SGD that are arranged along theY-direction are drawn out alternately four at a time to the twoX-direction sides of the stacked body 30.

Also, two source-side selection gates SGS that are adjacent to eachother in the Y-direction are connected to a common upper layer word line43 via the contacts 41 and are connected to one pad 64 via one contact63. Also, two word lines WL that are adjacent to each other in theY-direction are connected to a common upper layer word line 43 via thecontacts 41 and are connected to one pad 64 via one contact 63. However,the word lines WL that have mutually-different positions in theZ-direction are connected to mutually-different upper layer word lines43. Further, four drain-side selection gates SGD that are arranged alongthe Y-direction are connected to mutually-different pads 64 via thecontacts 41, the upper layer word lines 43, and the contacts 63. Thus,each of the electrode films 32 is connected to some pad 64 via thecontact 41, the upper layer word line 43, and the contact 63.

On the other hand, in the chip 102, a semiconductor substrate 12 that ismade of, for example, silicon is provided; and an inter-layer insulatingfilm 66 is provided on the semiconductor substrate 12. The transistors20 are formed inside the upper layer portion of the semiconductorsubstrate 12 and inside the inter-layer insulating film 66 and arearranged in a matrix configuration along the X-direction and theY-direction. In the chip 102, two transistors 20 arranged in the Xdirection constitute one group, and this group is periodically arrangedin the X direction. Also in such a case, it is assumed that thetransistors 20 are periodically arranged, and the arrangement period ofthe transistors 20 in each group is set as the minimum arrangementperiod of the transistor 20. The configuration of the transistor 20 issimilar to that of the first embodiment described above. Pads 67 areprovided in the upper layer portion of the inter-layer insulating film66. The pads 67 are formed of, for example, copper. The contacts 42 areconnected between the pads 67 and the lower layer interconnects 28.Thus, the diffusion region 22 of each of the transistors 20 is connectedto some pad 67 via the contact 27, the lower layer interconnect 28, andthe contact 42.

The chip 101 and the chip 102 are arranged so that the pads 64 and thepads 67 oppose each other; and the bumps 103 are bonded between the pads64 and the pads 67. The bumps 103 are bumps made of a conductivematerial and are, for example, solder balls. By the bumps 103, the pads64 are electrically connected to the pads 67; and the chip 101 ismechanically linked to the chip 102. Thereby, the electrode films 32 ofthe chip 101 are connected to the diffusion regions 22 of thetransistors 20 of the chip 102.

The length of a terrace T in the X-direction is determined by a periodP=MAX(P1, P2) which is the greater of a period P1 and a period P2, whereP1 is the minimum arrangement period of the pads 64 in the X-direction,and P2 is the minimum arrangement period of the transistors 20 in theX-direction. The length L1 of the terrace 33 a disposed in the region R1is shorter than the period P. Also, the length L2 of the terrace 33 bdisposed in the region R2 is longer than the period P. In other words,L1<P<L2.

Effects of the embodiment will now be described.

In the embodiment, the two chips 101 and 102 are provided; the stackedbody 30 is formed in the chip 101; and the transistors 20 are formed inthe chip 102. Thereby, compared to the case where both the stacked body30 and the transistors 20 are formed in one chip, the manufacturing iseasy; and the manufacturing cost is low.

Also, the layout of the upper layer word lines 43 can be simplifiedbecause it is unnecessary to provide the contacts 42 inside the chip101. Thereby, the layout of the upper layer word lines 43 is madeeasily; and the decrease of the operation speed due to the downscalingof the interconnects, the increase of the power consumption, and thedecrease of the reliability can be suppressed.

Otherwise, the configuration and the effects of the embodiment aresimilar to those of the first embodiment described above.

(First Modification of Ninth Embodiment)

A first modification of the ninth embodiment will now be described.

FIG. 28 is a plan view showing a chip in which the transistors of asemiconductor memory device according to the modification are formed.

FIG. 29 is a plan view showing a chip in which the stacked body of thesemiconductor memory device according to the modification is formed.

FIG. 30 is a cross-sectional view showing the semiconductor memorydevice according to the modification.

In the semiconductor memory device 9 a according to the modification asshown in FIG. 28 to FIG. 30, the chip 101 and the chip 102 are bonded byconductive pillars 104. The pillars 104 are made from, for example,copper; and the configurations of the pillars 104 are, for example,circular columns. The configurations of the chip 101 and the chip 102are similar to those of the ninth embodiment described above.

Otherwise, the configuration and the effects of the modification aresimilar to those of the ninth embodiment described above.

(Second Modification of Ninth Embodiment)

A second modification of the ninth embodiment will now be described.

FIG. 31 is a plan view showing a chip in which the transistors of asemiconductor memory device according to the modification are formed.

FIG. 32 is a plan view showing a chip in which the stacked body of thesemiconductor memory device according to the modification is formed.

FIG. 33 is a cross-sectional view showing the semiconductor memorydevice according to the modification.

As shown in FIG. 31 to FIG. 33, the chip 101 and the chip 102 aredirectly bonded in the semiconductor memory device 9 b according to themodification. For example, the chip 101 is linked to the chip 102 by abonding agent or mechanical method; and the pads 64 of the chip 101contact the pads 67 of the chip 102. The pads 64 and the pads 67 may bebonded by a conductive bonding agent. The configurations of the chip 101and the chip 102 are similar to those of the ninth embodiment describedabove.

Otherwise, the configuration and the effects of the modification aresimilar to those of the ninth embodiment described above.

According to the embodiments and the modifications of the embodimentsdescribed above, a semiconductor memory device can be realized in whichthe layout of the interconnects is easy.

The staircase along the Y-direction also may be formed in the endportion 30 a of the stacked body 30 of the first, third, fourth, andninth embodiments and the first and second modifications of the ninthembodiment.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the inventions. Indeed, the novel embodiments described hereinmay be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the embodimentsdescribed herein may be made without departing from the spirit of theinventions. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the inventions. Additionally, the embodiments and themodifications described above can be combined mutually.

What is claimed is:
 1. A semiconductor memory device, comprising: afirst chip; and a second chip, the first chip including a firstsemiconductor substrate having a first main surface extending in a firstdirection and a second direction, the second direction crossing thefirst direction, a stacked body provided on the first semiconductorsubstrate, the stacked body including a plurality of electrode filmsstacked to be separated from each other along a third direction, thethird direction crossing the first direction and the second direction, asemiconductor member piercing the plurality of electrode films in thethird direction, a charge storage member provided between thesemiconductor member and one of the plurality of electrode films, afirst pad, and a first contact connecting the one of the plurality ofelectrode films to the first pad, and the second chip including a secondsemiconductor substrate having a second main surface extending in thefirst direction and the second direction, a plurality of transistorsformed in the second main surface, a second pad, and a second contactconnecting one of a source/drain of one of the transistors to the secondpad, wherein the first chip and the second chip face each other suchthat the first pad is connected to the second pad, a configuration of anend portion in the first direction of the stacked body is staircase-likehaving a plurality of terraces, each of the plurality of terraces beingformed each of electrode films and the plurality of terraces including aplurality of first terraces and a second terrace, a second region andtwo first regions along the first direction are set in the end portion,the second region being disposed between the two first regions, theplurality of first terraces is disposed in each of the first regions,the second terrace is disposed in the second region, a length in thefirst direction of the second terrace is longer than the larger periodof a minimum period in the first direction of the first pads and aminimum period in the first direction of the plurality of transistors,and a length in the first direction of one of the plurality of firstterraces disposed in the first region is shorter than the larger period.2. The device according to claim 1, further comprising a bump connectedbetween the first pad and the second pad.
 3. The device according toclaim 1, further comprising a pillar connected between the first pad andthe second pad, the pillar being conductive.
 4. The device according toclaim 1, wherein the first pad contacts the second pad.
 5. The deviceaccording to claim 1, wherein the first chip further includes a bit lineconnected to an end in the third direction of the semiconductor member,the bit line extending in the second direction.
 6. The device accordingto claim 1, wherein the first chip further includes a first insulatingfilm formed to cover the first main surface of the first semiconductorsubstrate, the first pad being exposed from the first insulating film,and the second chip further includes a second insulating film formed tocover the second main surface of the second semiconductor substrate, thesecond pad being exposed from the second insulating film.
 7. The deviceaccording to claim 1, wherein in the first chip, the first contact isprovided in plurality correspondingly with the electrode films, and thefirst pad is provided in plurality correspondingly with the firstcontacts, and in the second chip, the second contact is provided inplurality correspondingly with the transistors, and the second pad isprovided in plurality correspondingly with the second contacts.
 8. Thedevice according to claim 7, wherein the first pads are arranged in anarray manner when viewed in the third direction, and the second pads arearranged in an array manner when viewed in the third direction.
 9. Thedevice according to claim 1, wherein the one of the plurality ofelectrode films is subdivided into a plurality of band-like portionsarranged along the second direction, and the first contact is connectedto a first band-like portion of the plurality of band-like portions. 10.The device according to claim 1, wherein the stacked body is subdividedinto a plurality of band-like portions arranged along the seconddirection, and a slit is formed between the band-like portions.
 11. Thedevice according to claim 1, wherein the plurality of transistors arearranged along the second direction.
 12. The device according to claim1, wherein the one of the plurality of electrode films is subdividedinto a plurality of band-like portions arranged along the seconddirection, and the plurality of band-like portions is connected to thesame transistor.
 13. The device according to claim 1, wherein the one ofthe plurality of electrode films is subdivided into a plurality ofband-like portions arranged along the second direction, and the firstcontact is connected to some of the band-like portions.
 14. The deviceaccording to claim 13, wherein the first contact is connected to amutually-adjacent plurality of the band-like portions and is notconnected to another mutually-adjacent plurality of the band-likeportions.
 15. The device according to claim 1, wherein the chargestorage member includes silicon and nitrogen.
 16. The device accordingto claim 1, wherein the charge storage member is conductive.